'Flat' feet is a widely used term to describe the structure of one’s foot. In many cases, people perceive they have flat feet, which in fact, is not usually the case. Generally, they will have a condition known as over pronated feet (e.g. the feet are rolling in when the person is standing, walking and/or running) and this will give the impression that the feet are flat. The foot structure is basically compensating for a particular condition. In most cases when you are in a non-weight bearing position (sitting) you will see an arch present in your foot. This shows that you don’t have structurally flat feet. However, when you stand you may have functionally flat feet due to too much pronation movement contributing to the lowering of the arch.
Pronation is basically the inward directed motion of the Talus bone which is the main structure governing the subtalar joint. When this joint moves inwards, excess forces are directed inwards causing the arch to collapse giving the appearance of a flat foot, thus termed functionally flat feet (not structurally flat feet). This causes the feet to become hyper mobile (excess movement). Pronation is essential for efficient walking and running as it absorbs shock and allows the foot to adapt to the terrain you are walking or running on. It is when this rotation becomes excessive and is present beyond the normal time period of the gait cycle that it can cause a vast array of symptoms, e.g. shin, knee and lower back pain.
In some cases the most effective treatment is the prescription of an orthotic which comes in a variety of forms depending on your weight, activity level, sports and the type of shoes you are going to wear them in. Shoes which are designed to reduce pronation have a limited impact in reducing this motion in some people if the pronation is excessive &/or they are too heavy.
Exercises can be given to reduce the amount of pronation of functionally flat feet. However, this isn’t an effective treatment regime in many cases as it doesn’t have any direct affect on the mechanism causing the pronation. By that I mean, there is no muscle and subsequently tendon controlling the direct function of the Talus bone (and subsequently the subtalar joint). Thus, exercises have a limited impact.
Strapping (i.e. Low Dye Technique) can also be effective in the treatment of mild cases for controlling adverse pronation. This is covered in the Strapping Techniques section of this site.